Compact component device for the visible display of letters, digits, symbols and figures

ABSTRACT

A compact component device for the visible display of letters, digits, symbols and figures characterized in comprising in combination a plurality of transparent plates mounted close to one another, a plurality of transparent rods passing through the pack of said plates through their thickness, one or more luminous sources located along one or more lateral faces of said pack, and means for selectively sending back the light from said sources along said rods, axialwise, so that the end front surfaces of said rods will form a unit of luminous zones on the front surface of said pack, reproducing the desired visible indication.

Inventors Maria Panerai;

Giuseppe Panerai, both of No. 2, Piazza Galileo Ferraris, Firenze, Italy Appl. No. 780,719 Filed Dec. 3, 1968 Patented Oct. 5, 1971 Priority Dec. 7, I967 Italy 819878 COMPACT COMPONENT DEVICE FOR THE VISIBLE DISPLAY OF LE'I'IERS, DIGITS,

SYMBOLS AND FIGURES 48 Claims, 59 Drawing Figs.

US. Cl. 340/380, 350/96 Int. Cl G08b 5/00 Field of Search 340/ 300; 350/96 [56] ham-re ains UNITED STATES PATENTS 3,353,026 1 l/ 1967 lsrealy 340/380 X 2,619,068 I l/l952 Malheiros et al. 340/380 X Primary Examiner-John W. Caldwell Assistant Examiner-Michael Slobasky Attorney-Wenderoth, Lind & Ponack ABSTRACT: A compact component device for the visible display of letters, digits, symbols and figures characterized in comprising in combination a plurality of transparent plates mounted close to one another, a plurality of transparent rods passing through the pack of said plates through their thickness, one or more luminous sources located along one or more lateral faces of said pack, and means for selectively sending back the light from said sources along said rods, axialwise, so that the end front surfaces of said rods will form a unit of luminous zones on the front surface of said pack, reproducing the desired visible indication.

PATENTEDUCT 5197i 3.611.359

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GIUSLPPE PANERAI INVENTORS ATTORNEY COMPACT COMPONENT DEVICE FOR THE VISIBLE DISPLAY OF LE'I'I'ERS, DIGITS, SYMBOLS AND FIGURES The present invention relates to a compact component device for the visible display of letters, digits, symbols and figures. I

In very numerous fields of the art there is the need of supplying a luminous indication or display, having an either fixed or variable composition. In some cases, such-as for instance the dials of electronic equipments, display panels, operative boards, etc., is it necessary to have a multiplicity of luminous signals contained in a rather restricted space. In the case of the advertising or informative luminous displays, where the problem of the dimensions is relatively less important, it occurs, however, the inconvenience of being compelled to have recourse to circuits and components very cumbersome, expensive and subject to frequent damages.

The purpose of this invention is that of embodying a device of the related kind, consisting of compact components (i.e. having minimum dimensions), having a simple constructive plan, a very high luminous yield, suitable to supply a large band of visible indications, having whatever sizes and colors with a power consumption remarkably lower than that of the known systems.

According to this invention, a device is provided including in combination, a plurality of transparent plates packed with one another, a plurality of transparent rods passing through the pack of said plates, through their thickness, one or more luminous sources located along one or more lateral faces of said pack, and means for returning selectively the light of said sources axialwise along the said rods so that the terminal surfaces of said bars will form a unit of luminous zones on the head surface of said pack, reproducing the desired visible indication.

In a first embodiment of this invention, said means for selectively returning the light consist of prismatic notches, provided along the rods in prefixed positions, so that by said plates will be returned by said prisms along the axis of the rods themselves, in order to form the preselected visible indication.

In a second embodiment of this invention, said means for the selective return of the light consist of two prismatic notches, opposite and symmetrical, which receive the light from two directions, or from a conical notch.

Always according to this invention, the light source or the light sources will move at will along the lateral faces of the block or pack of transparent plates, in order to send selectively a light beam to the plate corresponding to the selected indication.

According to a further embodiment of this invention each of said plates is provided along its contour one or more light sources, destined to be energized selectively to obtain on the front terminal surface of the rods the associated luminous indication.

In a variant, said means for the selective return of the light consist of prismatic notches, having a nonrelevant depth, provided in the lateral surface of the rods, perpendicularly to the optical axis and extending through one part or the entire contour of the rods themselves. SAid notches can be also provided in two half circles and axially staggered with respect to one another.

The depth of the various notches can be differentiated so as to avoid the possible screening effects with respect to the light rays which will be transmitted along the rods.

In another embodiment the means for the selective return of the light consist of a local restriction of a cross-sectional area of the rod, obtained so as not to change the optical features of the material in the restricted cross-sectional area zone. Said reastriction can be also obtained by symmetrical imprints obtained by deformation or by stretching.

In a further variant, the rods consist of segments of transparent material, located in prosecution with one another each having one bent at 90 so that the surface of said end will be presented towards the associated light source. Theend of each segment can be also U-bent'through a short length, and ending by a beveled portion forming a prism destined to feel and return the light of the associated source.

In another variant, suitable for rods the cross section of which is not circular, the light-retuming means consist of elementary prisms, bodily obtained on one or more side faces of the rod, and faced towards the respective light sources.

In another embodiment of this invention, the device includes an array of flexible light pipes, each having one end inserted in a front plate, and the other end faced to a cell containing one or more light sources, which are selectively energized in order to form, on said front plate the desired light display. The unit of the cells with their associated light sources (either incandescent or electroluminescent) is carried by a glidable frame, provided with sliding contacts for connecting the various control circuits, and easily dismountable .for quickly effecting the necessary checking, maintenance, and replacement of the light sources.

The prismatic notches provided in the transparent material rods can be surrounded by a ring of electroluminescent material, which is selectively energized by the operative circuits so as to illuminate said notches and send back the light to the front plate, in order to have a multiplicity of luminous zones forming the desired display.

In another embodiment there is an array of transparent pins, the head ends of which passes through the display front plate andthe side and bottom surface is rendered conductive by a transparent layer, with said bottom resting on a layer of electroluminescent material, which will be energized selectively in order to obtain the formation of desired luminous zones. The energizing circuits of the electroluminescent material layer include an opaque conductor layer, contacting said electroluminescent material, and a set of single conductors connected to the side conducting transparent surface of the pins through a metal ring. Said metal ring can advantageously consist of a conductive sleeve with an internal reflecting surface, surrounding the lateral surface of each pin.

In order to ensure the contact of the bottom surface of the various pins with the electroluminescent layer, an elastic layer is provided, resting in said conductive opaque layer thrusted and pushed towards it by a rigid plate. In order to render easily rechangeable the electroluminescent layer with its associated conductive support, said rigid plate is elastically thrusted by snap disengageable springs.

Alternatively, the layer of electroluminescent with its associated conductive support, are embodied in the fonn of a flexible tape coming from a bobbin, which is periodically displaced after the removal of the elastic pressure urging said tape against the bottom of the pins.

In another embodiment, said pins are made of conductiv opaque material, and are surrounded by a sleeve of transparent material. In this case, there is a plurality of luminous annular zones, corresponding to the zones where said electroluminescent layer is locally energized.

In a further embodiment, the panel is provided with a set of holes, through which it will be possible to see the corresponding luminous zones of the electroluminescent material, selectively activated by conductors having any shape and size, located below said electroluminescent layer.

In a further variant, a device is provided including in combination an array of transparent parallel rods, contained within a case and the front end of which is located in the visible plane or face of said casing, while the rear end is associated to a prism which receives the light from a horizontal electroluminescent plate. 1

In a further embodiment, said rods have difl'erentiated lengths, and their rear ends receive directly the light from electroluminescent vertical plates, partially overlapped on one another.

In another variant, the casing has its front face provided with an array of holes, behind which is located an electroluminescent panel, comprising a bottom conductor layer, an electroluminescent'material layer, and a set of conductive transparent zones, capable of'being-selectively-energized, and

located in register with said holes. The formation of luminous information will be obtained by energizing the electroluminescent layer in register with said transparent conductive zones, when the current is fed to said conductive zones according to an arrangement corresponding to the desired signal.

In another different embodiment, the device includes in combination a set of electroluminescent panels, closely standing and selectively energizable, located inside of a casing, and an array of transparent rods, perpendicularly located with respect to said panels, each of said rods having its front end appearing on a display plane, while the rear end of the rod rests on one of said panels, so that on said plane a number of luminous points will be observed, corresponding to the various energized panels.

In a further embodiment, a panel is provided including in combination, a multiplicity of metal zones, independent from one another, each carrying a conductor, a ceramic dielectric protective continuous layer covering the unit of said zones, a layer of electroluminescent phosphor superposed to said protective layer, a continuous transparent conductive layer to which is fastened a common electric conductor, and a front dielectric transparent protective layer, fonning the display face of the panel.

By selectively closing the circuits leading to said metal zones, the energizing of the corresponding zones of the phosphor layer will be obtained, whereby on the display of the panel a set of luminous points or zones, forming in their unit the desired indication.

Still according to this invention a process is provided for manufacturing the above disclosed panel, including the stages of: predisposing a continuous metal layer provided with a protective ceramic dielectric coating, superposing to said coating orderly, a layer of electroluminescent material, a transparent conductive layer and a protective transparent dielectric layer, removing by either electronical or mechanical or chemical means determined zones of said base metal layer so as to obtain a multiplicity of separate and independent zones, connecting said zones to a corresponding set of electric conductors for a selective energization, and connecting said transparent conductive continuous layer to a common conductor.

Still according to this invention, a device is provided allowing the quick and exact energization of a multiplicity of circuits according to a prefixed order, variable at will, in order to obtain on a luminous point board, a corresponding visible indication.

This device includes in combination; a multiplicity of female connection members, located on a control board reproducing the luminous point panel, and a set of male connection members, consisting of a socket provided with an array of contact jacks arranged to a predetermined design and suitable to energize the corresponding circuits of the panel due to the insertion into said female connection members in order to obtain on said panel a set of luminous points forming the desired indication.

Still according to the present invention, said control board is provided with a number of female connection members equaling that of the luminous points of the display panel, and said luminous points and said female members are grouped in zones (cells) ordered according to horizontal lines and vertical columns. In each of said zones of the board a male connection member can be applied the contact jacks of which will establish the formation of the set of luminous points forming the desired indication in the corresponding cell of the display panel.

This invention will be now described with reference to the attached drawings showing by way of nonlimitative example, a number of preferred embodiments of the invention itself.

In the drawings:

FIG. 1 is a diagrammatical representation, in cross-sectional view, of the device;

FIG. 2 is a partially cross sectional perspective view of a different embodiment of the device of FIG. 1;

FIGS. 3, 4 and 5 show some detail views of the various illumination systems;

FIG. 6 shows two examples of letteral display;

FIG. 7 shows a set of digital displays;

FIG. 8 shows an indication including more letters;

FIGS. 9 and 10 show two further kinds of elements for returning the light;

FIG. 11 shows the detail of one rod, in partial side elevation;

FIG. 12 is a cross-sectional view taken along the plane ll--II of FIG. 1;

FIGS. 13 and 14 show two views similar to FIG. 11, concerning two different embodiments;

FIG. 15 is a cross-sectional view taken along the plane V- V of FIG. 14;

FIGS. 16 to 22 diagrammatically show a set of different embodiments of the rod of FIG. 11;

FIG. 23 shows diagrammatically a further embodiment of the device according to the present invention, in vertical sectional view;

FIG. 24 shows a detail of the device of FIG. 23, in an enlarged scale;

FIG. 25 shows a cross-sectional view of a transparent rod with luminous collar;

FIG. 26 diagrammatically shows a cross-sectional of a view of a further embodiment;

FIG. 27 shows a different embodiment of the luminous pins of FIG. 26;

FIG. 28 diagrammatically shows the front view of the panel of FIG. 26;

FIGS. 29 and 30 show two different embodiments of the device of FIG. 26;

FIG. 31 shows a cross-sectional view of a further embodiment;

FIG. 32 is a partial front view ofthe panel of FIG. 31;

FIG. 33 shows a sectional view, taken along a vertical plane of a further embodiment;

FIG. 34 is a partially sectional perspective view of another panel according to this invention;

FIGS. 35 and 36 show a constructional detail;

FIG. 37 is a diagrammatical side elevation;

FIG. 38 is a view similar to FIG. 34 and showing another embodiment;

FIG. 39 is a view similar to FIG. 37;

FIG. 40 is a cross-sectional view of another embodiment;

FIG. 41 is a cross-sectional view taken along the plane VIII-VIII of FIG. 40;

FIG. 42 is perspective view, with some elements in exploded view, of another embodiment in perspective view;

FIG. 43 is a partially cross-sectional side elevational view;

FIG. 44 is a view similar to FIG. 42 showing a different embodiment of the device;

FIG. 45 is a perspective view of the device of FIG. 42;

FIG. 46 is a rear view;

FIG. 47 is a perspective view of a variant of the device of FIG. 42;

FIG. 48 is a cross-sectional view taken along the plane A- A of FIG. 45;

FIG. 49 shows a vertical sectional view of another panel according to this invention;

FIG. 50 is a partial rear elevational view of the panel of FIG. 49;

FIG. 51 shows a variant of FIG. 50;

FIG. 52 shows a front view of the panel;

FIGS. 53 and 54 show a variant to the FIGS. 49 and 50;

FIG. 55 diagrammatically shows a control unit for digital panels;

FIG. 56 is a detail view showing the connections between one zone or cell of the control board;

FIG. 57 shows the detail ofa male connecting member;

FIG. 58 shows the detail of the control boards with the receiving recesses of the male connecting members;

FIG. 59 is a detail view of the control board of FIG. 58.

With reference to FIG. 1, this invention provides a set of transparent plates I, packed along their faces 2 so as to form a pack which extends from the front or display face 3 to the rear face 4. On the front face 3 and on the separating faces 2 an opaque material-coating layer 5 can be provided.

The pack of plates 1 is passed through by a set of rods 6, also made of transparent material, provided with prismatic notches 7 located according to the conformation of the visual display to be obtained. In other words, the notches 7 form in the plane of each plate 1, one letter, digit, symbol or sign to be obtained; therefore, the device of FIG. 1 lends to production of a number of indications equaling the number of plates. In FIG. 1 l0 plates 1 have been shown, being however understood that their number can change within limits rather broad.

Along one or more sides of the pack of plates 1, a light source 8 movable towards the two directions shown by the arrows, is located, and said source consists of one or more incandescent of fluorescent or luminescent, and so on, elements. The light source 8 is contained in a recess 9 provided with an optical condenser 10, if the case may be, and serves the function of sending a light beam having a thickness substantially equal to the thickness of one plate 1.

The operation is as follows: the light beam coming from the light source or sources 8 passes through the transparent plate 1 and the rods 6 along the path as shown by the arrows, will be sent back by the prismatic notches 7 axialwise along the rods, emerging from the front end surfaces 11 in the form of luminous zones either white or colored, having the desired location. In FIGS. 6 and 7 some digital or letteral indications have been shown by way of example, while in FIG. 8 a group of luminous indications suitable to form a word, has been shown. It is evident that according to the number of the plates 1 and of the rods 6 it will be possible to obtain from a single compact pack or from more blocks sequentially located, one wording, one number or any figure.

As shown in FIG. I, the terminal surfaces 11 of the rods 6 can be conveniently shaped with concentrical steps, in order to afford a good visibility even under a visual angle somewhat displaced with respect to the front observation of the front or display face 3, being however understood that the surfaces 1 1 can be lens-shaped or flat-shaped; also the front end of the rods can slightly project out from the plane 3 (as in FIG. 1) or it can be at level of said plane, or also be somewhat embedded.

In the variant shown in FIG. 2 each plate 1 is provided with a peripheral recess 12 wherein is located a set of light sources 13 or a single source 14 for each side of the plate. The sources 13 and 14 are fed by the conductors 15 leading to the terminal board 16. In this case, the luminous indications are obtained by selectively switching on said sources.

In FIG. 3, the light sources are embodied by an electroluminescent layer 17, while in FIG. 4 the light of the electroluminescent layers 17 is returned by a total reflection prismatic surface 18, provided along the edge of the plate 1.

In the variant of FIG. 5, the light sources consist of tubular elements 19 interposed between the plates 1. The latter, in this case, will be spaced apart by means of opaque sleeves 20 serving the purpose of preventing the possible luminous interferences.

Instead of the prismatic notches 7 it is possible to sue also returning surfaces consisting of two prismatic surfaces 7' and 7" symmetrical and opposite (FIG. 9) which receive the light from two reverse directions, or (FIG. 10) the return of the luminous rights can be obtained also by a conical surface 7 For simplicity of showing, the cross-sectional shape of the rods 6 is circular, being however understood that said rods can have also a quadrangular or polygonal cross-sectional shape.

In FIGS. II and 12, the numeral reference 21 denotes the transparent rod, having an indefinite length, with a circular cross-sectional shape. The means for the selective return of the light, coming from one or more sources 23, can consist of a little deep prismatic notch 22 extending through one half circumference of the rod itself, as shown in FIG. 12, or throughout the circumference. as shown in FIG. 13.

FIGS. 14 and 15 have two semicircumferential prismatic notches 24 and 25, slightly staggered axialwise, while in FIG. 16, the return means of the light coming from the sources 23 consist of two symmetrical imprints 26 obtained by locally deforming the rod 21 producing no variation of the optical features of the material forming the rod itself. Said imprints can be embodied in the shape of prismatic notches 27 (FIG. 17) or of biprismatic notches 28 (FIG. 19). In FIG. 18 a gradual restriction of the cross-sectional area 29 is shown, obtained by hot stretching.

In FIG. 20, the rod 21 for the transmission of the light, is subdivided into various segments aligned along the optical axis. Each segment is provided with one end 30 bent at right angle, and turned towards the light source 23.

In FIG. 21 the end of each segment 21 is U-bent and is provided with a prismatic terminal face 31 which is hit by the light coming from the associated source 13. All embodiments shown in FIGS. 16 to 21 can be embodied with transparent rods having a circular or prismatic cross-sectional shape (triangular, quadrangular, polygonal, etc.

In case of rods the cross-sectional shape of which is not circular, also the variant of FIG. 22 can be adopted, consisting of a prism 32 bodily obtained in the material forming the rod 21, on one or more side faces.

It is to be noted that for sake or simplicity of showing, the light sources 23 have been shown diagrammatically under the form of a lamp, being however understood that the light source can also be of another kind, for instance an electroluminescent zone.

Another embodiment of the device according to this inven tion is shown in FIG. 23; in this case, the light-transmitting elements consists of an array of flexible light pipes 33, coated with an opaque layer 34.

The light pipes 33 have one end 35 inserted into the holes 36 of the front plate 37 (forming the luminous display panel), while the other end 38 is faced to the holes 39 provided through the plate 40. i

The holes 39 are located in exact register with an array of cells 41 separate by partitions 42 and containing the light sources 43.

In order to enable quick and easy operations for checking and replacing the light sources 43, the insulating support 44 of said sources and the plate 40 form an extractable drawer as shown in dotted line in FIG. 23, by a handle or the like 45.

In order to allow said drawer to be extracted, the conductors 46 of the sources 34 end by the sliding contacts 47, faced to the lower surface of the insulating support 44 and cooperating with the respective spring contacts 48 carried by the stationary insulating support 49.

The contacts 48 are connected to the feeding conductors 50 leading to the operative circuits which will not be described as they are not part of this invention.

The operation is similar to the already described one; the operative controls will switch on the sources 43 according to the desired sequences, and on the surface of the front plate 37 a multiplicity of luminous points will be obtained forming the desired visible display.

It is to be noted, in this connection, that each cell 41 two or more light sources 43 can be located, with various colors if the case may be, in order to obtain the luminous display on the front plate 37 in various colors.

The embodiment of FIG. 23 lends also to its embodiment rigid rods of transparent material, bent as shown in the figure.

As shown in FIG. 24 instead of the cited pointlike light sources, it is possible to locate within the cells 44 little elec troluminescent panels 51.

In this case, the holes 39 of the plate 40 can have conveniently a conical shape, in order to receive entirely the amount of light emitted by the panels 5 1.

With reference to FIG. 25, 'the numeral reference 52 denotes the rod transparent material, provided with a set of prismatic notches ,53, which partially or entirely extend on the side surface of the rod, as aforesaid. 

1. A device for the visible display of letters, digits, symbols and figures, comprising in combination a plurality of transparent plates mounted adjacent one another to form a pack, a plurality of transparent rods passing through said pack in their thickness direction, one or more luminous sources locates along at least one lateral face of said pack to illuminate the corresponding plate and means for selectively reflecting the light from said sources axially along said rods, so that the end front surfaces of said rods will form a unit of luminous zones on the front surface of said pack, reproducing the desired visible indication.
 2. A device as claimed in claim 1, wherein said selective reflecting means for the light comprises prismatic notches provided along the rods in prefixed positions whereby a light beam, perpendicular to the axis of the rods, guided by said plates, will be reflected at least by one of said prismatic notches along the axes of the rods themselves, in order to supply the selected visible display.
 3. A device as claimed in claim 2, wherein said means for selectively reflecting the light comprise two prismatic opposite and symmetrical notches, which receive the light from two opposite directions.
 4. A device as claimed in claim 1 wherein said means for the selective reflecting the light comprise a notch having a conical shape.
 5. A device as claimed in claim 1, wherein said luminous source is movable along the lateral faces of said pack to selectively send a light beam to the plate corresponding to the selected indication.
 6. A device as claimed in claim 1, wherein each of said plates is provided along at least one lateral side thereof with at least one luminous source to be energized selectively in order to have on the front end surface of the rods a luminous indication.
 7. A device as claimed in claim 6, wherein said luminous sources are arranged within recesses provided along the edges of said plates.
 8. A device as claimed in claim 1, wherein said light source is a lamp selected from a group consisting of incandescence, luminescence and electroluminescence lamp types.
 9. A device as claimed in claim 1, wherein said light source is a layer of electroluminescent material.
 10. A device as claimed in claim 9, wherein said layer of electroluminescent material is applied along the edge of each plate, in a position adjacent to a prismatic surface in the thickness of the plate itself.
 11. A device as claimed in claim 2, wherein said light sources are interposed between said plates adjacent said prismatic notches, said plates being spaced apart by means of opaque sleeves, surrounding the corresponding zones of the rods.
 12. A device as claimed in claim 1, wherein said selective reflecting means for the light comprise prismatic notches having a slight depth in the side surface of said rods, perpendicularly with respect to the optical axis, and extending at least partially about the contour of the cross section of said rods.
 13. A device as claimed in claim 12, wherein said notches are provided on two half-circumferences axialwise staggered with respect to one another.
 14. A device as claimed in claim 1, wherein said rods are subdivided into sections located in alignment with one another, and each having one end bent perpendicularly with respect to the optical axis, so that the head surface of said end will be facing towards the associated light source.
 15. A device as claimed in claim 14, wherein the end of each segment is U bent through a short portion, and ends with a face forming a prism destined to reflect the light of the associated source.
 16. A device as claimed in claim 1, wherein said rods comprise an array of flexible light pipes, each having one end inserted through a front plate and the other end faced circuits, a cell containing one or more light sources, selectively energized in order to form, on said front plate, the desired luminous indication.
 17. A device as claimed in claim 16, wherein said cells with their associated light sources is carried by a slidable frame, provided with sliding contacts for the connection with the control circuits, and easily removable for checking and replacing the light source.
 18. A device as claimed in claim 16, wherein in each cell are contained at least two light sources, having various colors, in order to obtain on the front plate a colored luminous display according to various colors.
 19. A device as claimed in claim 1, wherein said light source consists of an electroluminescent plate.
 20. A device as claimed in claim 12, wherein the prismatic notches provided on the transparent material rods are surrounded by a ring of electroluminescent material to be energized selectively by the operative circuits, for selectively illuMinating said notches and for reflecting the light to the front end of the rods.
 21. A device as claimed in claim 20, wherein a layer of electroluminescent material is contained between a transparent conductive coating applied to the lateral surface of the rod, and a conductive sleeve surrounding the zone of each prismatic notch.
 22. A device as set forth in claim 1 comprising a multiplicity of female connection elements located on a control board reproducing the luminous point panel, and a set of male connectors, consisting of a socket provided with a set of contact jacks located according to a prefixed design, suitable to energize the corresponding circuits of the panel due to insertion into said female connectors in order to obtain on said panel a set of luminous points forming the desired indication.
 23. A device as claimed in claim 22, characterized in that said control board is provided with a number of female connector members equaling the number of the luminous points of the display panel.
 24. A device as claimed in claim 23, characterized in that the display board is subdivided into zones or ''''cells'''' each of which includes a plurality of luminous points, orderly located in lines and columns, and the control board is subdivided into a corresponding number of zones, into each of which a male connector element can be inserted.
 25. A device as claimed in claim 24, characterized in that said control board is provided with Cartesian references suitable to allow the immediate and easy individuation of the various corresponding cells on the luminous panel, and is provided with a set of cases provided with references and destined to contain said male connectors.
 26. A device as claimed in claim 1, characterized in comprising an array of pins of transparent material having their head end passing through the display front plate, and the lateral and rear surfaces rendered conductive by a transparent layer, said rear end resting on a layer electroluminescent material, which will be selectively energized in order to obtain the formation of the desired luminous zones.
 27. A device as claimed in claim 1, characterized in that the means for the selective energization of said electroluminescent layer include an opaque conductive layer, located below said electroluminescent layer, and a set of single conductors connected to the conductive lateral surface of the associated pin, through a metal ring.
 28. A device as claimed in claim 27, characterized in that said metal ring consists of a conductive sleeve with a reflecting surface, which entirely or partially surrounds the lateral surface of the pin.
 29. A device as claimed in claim 28, characterized in that said electroluminescent layer is pressed against the rear end of the pins by an elastic layer, interposed between said opaque conductive layer and an outer rigid plate.
 30. A device as claimed in claim 29, characterized in that said outer plate is elastically urged by one or more snap springs, in order to render said electroluminescent layer and its associated opaque conductor, easily rechangeable.
 31. A device as claimed in claim 3, characterized in that the electroluminescent layer with its associated continuous opaque conductive support is embodied in form of a flexible tape, which is elastically pressured against the rear end of said pins, and can be moved periodically under a control, from feeding bobbin to a collecting bobbin for the exhausted tape.
 32. A device as claimed in claim 31, characterized in that said pins are made of opaque conductive material, and are surrounded by sleeves of transparent material.
 33. A device as claimed in claim 31, characterized in that said front plate is provided with a set of holes communicating with a diffuser transparent layer resting on a transparent conductor, below which are arranged a layer of electroluminescent material and a set of single conductors which can be selectively energized and are located in alignment with said holes.
 34. A device as claimed in claim 33, characterized in comprising in combination a set of parallel transparent rods, contained within a casing and the front end of which is located in the front plane or display face of said casing, while each of their rear ends is associated to a prism receiving the light from an electroluminescent horizontal plate.
 35. A device as claimed in claim 34, characterized in that said electroluminescent plates are fed by a common conductor and by a selectively energized conductor associated to each single plate and ending to a quick connection element with the operative circuits.
 36. A device as claimed in claim 35, characterized in that said rods have a differentiated length and their rear ends receive directly the light from a set of electroluminescent vertical plates, partially superposed to one another.
 37. A device as claimed in claim 36, characterized in that the casing has a front plate with an array of holes, behind which is located an electroluminescent panel including a bottom conductive layer, a layer of electroluminescent layer and a set of selectively energizable transparent zones, located in register with said holes.
 38. A device as claimed in claim 37, characterized in that said transparent conductive zones are carried by a transparent insulating plate, interposed between the apertured front plate and the layer of electroluminescent material.
 39. A device as claimed in claim 38, characterized in that the selective operation conductors are connected to said single transparent conductive zones, while the common conductor leads to said bottom conductive layer.
 40. A device as claimed in claim 39, characterized in that said conductors lead to a quick connection element connected to the operative circuits.
 41. A device as claimed in claim 40, characterized in comprising a set of electroluminescent panels close mounted to one another, selectively energizable and located inside of a casing, and an array of transparent rods, located perpendicularly to said panels, each of said rods having its front end appearing on a display plane, and its rear end resting on one of said panels, so that on said plane a set of luminous points will be observed, corresponding to the various energized panels.
 42. A device as claimed in claim 41, characterized in that each rod or transparent pin passes through a hole provided in the set of preceding panels.
 43. A device as claimed in claim 42, characterized in that the front ends of the pins appear through a set of holes provided through a front plate forming the display plate.
 44. A device as claimed in claim 43, characterized in that the unit of the panels and pins is contained within a casing provided frontally with said display plate and provided at its other end with a terminal unit connecting the feeding conductors of the various panels to the operative circuits.
 45. A device as claimed in claim 44, characterized in that the unit of the panels is subdivided into horizontal stripes and vertical columns, each of which carries the set of associated pins.
 46. A device as claimed in claim 45, characterized in comprising in combination a multiplicity of metal zones independent from one another, each provided with a conductor, a continuous protective dielectric ceramic layer covering the unit of said zones, a layer of electroluminescent material superposed to said protective layer, a continuous transparent conductive layer to which an electric common conductor is fastened and a front dielectric protective layer, forming the display face of the panel.
 47. A device as claimed in claim 46, characterized in that said ceramic protective dielectric layer is bodily embodied with the independent metal zones.
 48. A device as claimed in claim 47, characterized in that said electroluminescent material consists of a homogeneous paste of finely subdivided phosphor and power of ceramic material. 